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3. Compare the ampere rating on the starter nameplate to
rating on the compressor nameplate. The overload trip
amps must be 108% to 120%of the rated load amps.
4. The starter for a centrifugal compressor motor must
contain the components and terminals required for PIC
II refrigeration control. Check the certified drawings.
5. Check the voltage to the following components and
compare it to the nameplate values: pumpout compres-
sor starter and power panel.
6. Ensure that fused disconnects or circuit breakers have
been supplied for the power panel and pumpout unit.
7. Ensure all electrical equipment and controls are prop-
erly grounded in accordance with job drawings, certi-
fied drawings, and all applicable electrical codes.
8. Ensure the customer's contractor has verified proper
operation of the pumps, cooling tower fans, and asso-
ciated auxiliary equipment. This includes ensuring
motors are properly lubricated and have proper electri-
cal supply and proper rotation.
9. For field-installed starters only, test the chiller com-
pressor motor and its power lead insulation resistance
with a 500-v insulation tester such as a megohmmeter.
(Use a 5000-v tester for motors rated over 600 v.) Fac-
tory-mounted starters do not require a megohm test.
a. Open the starter main disconnect switch and fol-
low lockout/tagout rules.
If the motor starter is a solid-state starter, the motor leads
must be disconnected from the starter before an insulation
test is performed. The voltage generated from the tester can
damage the starter solid-state components.
b. With the tester connected to the motor leads, take
10-second and 60-second megohm readings as
follows:
6-Lead Motor — Tie all 6 leads together and test
between the lead group and ground. Next tie the
leads in pairs: 1 and 4, 2 and 5, and 3 and 6. Test
between each pair while grounding the third pair.
3-Lead Motor — Tie terminals 1, 2, and 3 together
and test between the group and ground.
c. Divide the 60-second resistance reading by the
10-second reading. The ratio, or polarization
index, must be one or higher. Both the 10- and
60-second readings must be at least 50 megohms.
If the readings on a field-installed starter are
unsatisfactory, repeat the test at the motor with the
power leads disconnected. Satisfactory readings in
this second test indicate the fault is in the power
leads.
NOTE: Unit-mounted starters do not have to be
megohm tested.
10. Tighten all wiring connections to the plugs on the ISM
and CCM modules.
11. Ensure that the voltage selector switch inside the
power panel is switched to the incoming voltage
rating.
On chillers with free-standing starters, inspect the
power panel to ensure that the contractor has fed the
wires into the bottom of the panel. Wiring into the top
of the panel can cause debris to fall into the contactors.
Clean and inspect the contactors if this has occurred.
Carrier Comfort Network Interface —
Comfort Network (CCN) communication bus wiring is
supplied and installed by the electrical contractor. It consists of
shielded, 3-conductor cable with drain wire.
The system elements are connected to the communication
bus in a daisy chain arrangement. The positive pin of each sys-
tem element communication connector must be wired to the
positive pins of the system element on either side of it. The
negative pins must be wired to the negative pins. The signal
ground pins must be wired to the signal ground pins. See instal-
lation manual.
NOTE: Conductors and drain wire must be 20 AWG (Ameri-
can Wire Gage) minimum stranded, tinned copper. Individual
conductors must be insulated with PVC, PVC/nylon, vinyl,
Teflon, or polyethylene. An aluminum/polyester 100% foil
shield and an outer jacket of PVC, PVC/nylon, chrome vinyl,
or Teflon with a minimum operating temperature range of –4 F
to 140 F (–20 C to 60 C) is required. See table below for cables
that meet the requirements.
MANUFACTURER
When connecting the CCN communication bus to a system
element, a color code system for the entire network is recom-
mended to simplify installation and checkout. The following
color code is recommended:
SIGNAL TYPE
Ground
Check Starter
BE AWARE that certain automatic start arrangements can
engage the starter. Open the disconnect ahead of the starter
in addition to shutting off the chiller or pump.
Use the instruction and service manual supplied by the
starter manufacturer to verify the starter has been installed cor-
rectly, to set up and calibrate the starter, and for complete trou-
bleshooting information.
The main disconnect on the starter front panel may not
deenergize all internal circuits. Open all internal and
remote disconnects before servicing the starter.
MECHANICAL STARTER
1. Check all field wiring connections for tightness, clear-
ance from moving parts, and correct connection.
2. Check the contactor(s) to ensure they move freely.
Check the mechanical interlock between contactors to
ensure that 1S and 2M contactors cannot be closed at
the same time. Check all other electro-mechanical
devices, such as relays, for free movement. If the
devices do not move freely, contact the starter manu-
facturer for replacement components.
3. Some dashpot-type magnetic overload relays must be
filled with oil on the jobsite. If the starter is equipped
with devices of this type, remove the fluid cups from
these magnetic overload relays. Add the dashpot oil to
The Carrier
the cups according to the instructions supplied with the
starter. The oil is usually shipped in a small container
59
Alpha
American
Belden
Columbia
CCN BUS CONDUCTOR
INSULATION COLOR
Red
+
White
Black
–
CABLE NO.
2413 or 5463
A22503
8772
02525
CVC PLUG J1
PIN NO.
1
2
3
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